Challenge Accepted
by Eri-Kumiko
Summary: Kaidou Kaoru made an acquaintance of one Echizen Ryoma, and slowly a friendship of a kind was formed. Yet, after more time passes, Kaidou becomes less and less certain what his mysterious junior wants from this friendship... if it can be labeled as that anymore.
1. Prologue

_The sound of sneakers squeaking against the court and rackets hitting their target filled up the air. A few taunts were exchanged between the regulars every now and then to break the perfect harmony created by the sounds of tennis._

_"Hah! Try to return this, Echizen!"_

_"Not good enough, Momo-senpai."_

_"ARGH-"_

A young boy adjusted his position on the bench as he watched the practice game taking place before him, a corner of his lips lifting up unconsciously. The contrast between the cool freshman and over-expressive senior was straight-up comical, sometimes to the point of distracting viewers from the match itself.

"You're in a good mood, Kaidou-kun."

In a split second the ghost of a smile was gone, replaced by a sullen expression and a threatening glare. It was just like Inui to be able to tell the slight changes on the second-year's face apart.

As the glare proved to be ineffective against his senior, Kaidou let out a quiet hiss as he sunk lower in his seat, his bad posture turning even worse. He didn't grace Inui with an answer, which he had probably calculated anyway.

Kaidou knit his brows further together as he realized he'd missed the finishing shot of the match, causing him to mentally stab Inui. The loss didn't trouble him long, though, as he studied the smug smile on his junior's face. It was quite easy to tell who won.

Feeling the gaze on him, Echizen turned his golden orbs on Kaidou, both determined and curious. Neither being able or willing to turn away, together they stared at each other, creating an odd sense of tension around them.

The magic was broken by none other than Momoshiro. He lowered his head on Echizen's level and cupped his hand next to his ear, whispering while giving a suspicious look at the boy known as the Viper. "Hey, did you do something to piss him off? He looks even uglier than usual."

Echizen swatted the hand that violated his personal space away and rubbed his ear with a hint of disgust on his face. He raised up his racket and rested it against his shoulder as he shrugged and took his first step towards the benches. "I suggest you take a look in the mirror, Senpai."

Rolling his eyes at Momoshiro's bellowing about "no respect towards his seniors", Echizen hurried his steps as he noticed Kaidou getting up and starting to gather his things. How Inui slunk away due to his approach went unnoticed.

"You're not playing today, Kaidou-senpai?"

The senior grunted under his breath as he removed his jacket and threw a towel around his neck instead. "Already did."

A blank stare. As no other reply was given, Echizen continued; "Going on a run, then?"

A pause. Kaidou looked down, finally meeting the other's eyes. The stare was so keen he kind of felt like he was being challenged. "Hn," he replied, as his way of saying 'yeah', and glared a bit harder. He felt a little disappointed that it didn't seem to have effect on anyone today.

Again, they stared at each other in a short silence before Echizen questioned him again. "Will you come to see Karupin after you're done?"

This caused his senior to glance away, a slight tint of red on his cheeks. He picked up his bag and cleared his throat, eyeing at the sky like something interesting would have been up there. "Could be."

A heavy silence fell on them once more. As neither of them attempted to move, Kaidou gave up and looked back down, for the final time. Echizen was still staring up at him with steely eyes, expression serious as ever. He really felt like he was being challenged.

"No one else is at home."

And so, the gauntlet was thrown.


	2. Another Challenger

**AN: **_Jinbei is japanese clothing for men that's worn only at home; also as pajamas._

Kaidou gave an incredulous look at the boy before him. If he could have been able to frown any further, he would have. "Hah?" He voiced out, and immediately wished he'd stayed silent. His voice seemed to have adopted a surprisingly high pitch, which didn't suit him at all.

Echizen snorted at that, mischief visiting his eyes for a fleeting moment. He reached up to poke at his senior between the brows, where his almost permanent frown had formed a deep dent.

"Hey, hey. You'll look like an old man if you keep making scary faces like that."

Kaidou turned his head abruptly out of his junior's reach, grumbling at the remark. "Hmph. Arrogant brat." He swung his bag over his shoulder and turned his back on the other, suggesting that this conversation was over.

Naturally, Echizen had none of that. He wanted to have the last word.

"I'll be waiting for you, Kaidou-senpai."

Briefly, Kaidou stopped on his tracks. There was something about that tone that both intrigued and annoyed him. He turned ever so slightly, an unreadable expression decorating his face. He wasn't exactly sure what was going through his mind, nor what he wanted to say, yet there was something about the boy's odd behaviour that was completely new... and so very curious.

"Na, Echizen. Leave the Viper alone so we can go eat. I'm hungry..."

He would never mistake that voice. That damn voice. A choking sound formed in his throat as Kaidou felt the familiar feeling of bottled up anger arise, ready to be unleashed. His neck cracked painfully as he turned to look at Momoshiro's direction, a hiss escaping through his teeth.

"What was that, you bastard?! What did you call me?!"

Momoshiro shrugged lazily and leaned forward, further taunting the enraged boy. "Are you going deaf, Viper? I said Viper, _Viper_"

When Kaidou let his bag fall on the ground and approached the other in a threatening manner, Echizen stepped between the two and placed a calm yet firm hand on Kaidou's chest.

"Senpai."

Kaidou _wanted _to tell his junior to back off, but he fell silent as he met his eyes. It was the same bored, almost apathetic look that Ryoma tended to give, but somehow he found himself unable to shove him away. "Che," he spat and glanced at the ground.

A brief silence fell on them as each of them studied one another. Momoshiro at Ryoma, Ryoma at Kaidou, and Kaidou, well, at his sneakers.

"Hm?" If he'd said he wasn't curious about the situation at hand, Momoshiro would have been lying. Yet, that wasn't the only emotion emerging. The other one was much stronger and uglier, one that twisted the pits of his stomach. "Since when did you become a snake charmer, Echizen?" His throat was suddenly dry, and the mocking voice that left him wasn't his own.

Kaidou immediately looked back up to glare at him in the meanest way possible, but surprisingly, Ryoma just let out a quiet laughter.

Both seniors stared down at the boy between them, lips slightly parted in awe.

"Hm, no, Momo-senpai." He smiled wryly before glancing at Kaidou, his laughter dying down. That same mischief was in his eyes again. "I still have ways to go."

For unknown reasons, Kaidou's breath halted and turned into a quiet gasp. Something about Echizen's presence caused him to feel these strange things lately, and he had no idea what it was. All he knew was that it made him terribly uncomfortable and contradicted with himself, and it made his fight or flight instinct to kick in.

And right now, Echizen was the stronger of the two.

He sent one more dirty look Momoshiro's way before taking a step back. "I have ten kilometres to run." He whispered hoarsely and grabbed his bag, dusting it off. Without giving the others a chance to say anything, he picked up his pace and began to jog off.

Momoshiro decided to take it as his victory as he watched the Viper go, or escaping, like he wanted to think. A toothy grin appeared on his face as he patted Ryoma's back. "Hah, now that we got rid of that one, why don't we- "

His words died in his throat as the expression on Ryoma's face shattered his heart into tiny pieces.

His junior still stared after Kaidou, his eyes somehow lonely and painful. He frowned in a way only a stubborn child could, and as he normally would have cracked a joke about that, now he couldn't.

He knew that there was something between the two, but what it was, exactly... that was a thought he didn't dare to delve too deeply.

"Echizen- "

Just as he was about to suggest they'd take their leave, Ryoma suddenly broke into a run. His footsteps were quick and light as he approached the person already gone far ahead, and only stopped when he was within earshot. He gathered as much air in his lungs as he could and shouted after him,

"Senpai! Remember to bring your jinbei!"

Just like he'd expected, Kaidou didn't stop. But what he didn't expect, was that he raised his hand and waved it slightly as a sign of understanding. A silly smile broke on the younger boy's face as he plopped down on the court, slightly out of breath.

Another thing he didn't expect, nor notice, was the look of disapproval on Momoshiro's face. The thought that he tried to keep away stubbornly rose on the surface.

Still smiling to himself, Ryoma got up on his feet and slowly sauntered back. He swiped his hand over his face and massaged his cheeks with his fingers, attempting to get rid of the smile that wouldn't leave his lips.

He walked past Momoshiro, and for a moment he wasn't sure where he was going. When he heard no footsteps behind him, he glanced back and casually called after his senior. "The first one at the restaurant gets free burgers."

The older boy didn't really register the words at first, but as his junior broke into a run yet again, he snapped out of his trance as a sense of panic formed inside him. "W-Wait!" He uttered and ran after him as quickly as he could.

Only the sounds of hurried footsteps and muttering of no respect could be heard on that otherwise quiet afternoon.


	3. Wrong Opponent

"Thank you for the treat, Senpai!"

"H-Hah... you cheated, cheeky brat!"

Leaning against the window of the restaurant, Echizen smiled impishly and stuck his tongue out. He was just as out of breath as his companion, but hell if he would show it. "Or maybe you're just a sore loser." He replied, his voice nasal.

"Tch. A tiny bug like you shouldn't even be that fast. My legs have way more reach." Momoshiro sighed and brought up a hand to swipe over his sweaty brow. He pushed his junior out of the way not-too-gently and opened the glass door, admitting his defeat.

Pleased with his victory, Echizen followed after him and adjusted his cap, a smirk plastered on his face. "You still have ways to- " His eyes widened and he stopped on his tracks, his words turning incoherent.

Raising a brow, Momoshiro turned to look at his friend; or, his back, more like.

"I've got things to do." Echizen deadpanned and grit his teeth together when a screeching voice reached his ears.

"Ryoma-sama! Ryoma-sama!"

Both Seigaku regulars cringed at the sound and fled out of the restaurant as an unspoken deal. A disappointed squeal could still be heard several feet away, even if they tried to run as fast as their legs would carry.

"I've lost my appetite." They spoke at the same time, completely defeated, and slumped to the ground shoulder to shoulder.

Momoshiro bumped his head against Ryoma's, and came to regret it as a small sting went through his skull. "Argh, why did you have to lure your fanclub into my favourite place, _Ryoma-sama_?" He spoke accusatively and sulked.

Feeling his brow twitching as he grew more annoyed, Ryoma gave a forceful shove at his senior's shoulder, who somehow managed to keel over and land on his face. What he mumbled with his mouth full of dirt, was unclear. The younger boy got up on his feet and gave a pitying glance at the suffering figure on the ground before walking off.

"It's regrettable, but I guess I have to cook tonight." He muttered, mostly to himself.

"Stupid shrimp, absolutely no respect..." Momoshiro fumed as he scrambled up and jogged after the other, delivering a slap at the back of Ryoma's head. He decided to ignore the boy's complaining, no matter how much his pouting face made him want to apologize. He bit his lower lip, thoughtful, before speaking up again. "You could come to our house, I mean, my mom always cooks too much."

He was rejected in an instant. "No can do. Kaidou-senpai is coming over." Voice loud and clear, it was like a proud announcement.

That serene gaze at particularly nowhere made the senior feel devastated once again during the same day. He felt an uncomfortable twist in his gut, and he was unable to stop the sour words spilling out of his mouth.

"Kaidou schmaidou," he sneered, "Lately that viper's been all you've talked about."

"Well yeah." Ryoma responded casually, completely missing the mocking tone. "He's my friend, after all."

"_I'm _your friend and you never fuss over me."

"He's good at tennis."

"_You haven't even played against him since Winter!"_

"Karupin likes him."

"_HE'S ALWAYS COVERED IN SCRATCHES WHEN HE LEAVES YOUR HOUSE!"_

Ryoma couldn't help but to snicker at the thought. It was an undeniable fact. He glanced at his friend, who was suddenly really out of breath from yelling. How he got worked up so easily never failed to amuse the boy.

Shrugging, Ryoma took a better grip of his bag and smiled softly as he looked forward.

"Maybe _I _like him."

Momoshiro was ready to state another counter, yet his mind drew a complete blank on this one. Baffled, he stared at the younger boy with his mouth hanging open. When Ryoma registered the silence, he glanced over at his friend and frowned.

"Stop that, you look like a puffer fish."

Immediately closing his mouth and glaring at him, Momoshiro was very tempted to hit him again.

He tried to speak but no words would come out.

This was the topic he was so interested in and so afraid of. That was the answer he had been looking for and avoiding for so long. Suddenly, he felt like his head was spinning and he wanted to vomit. He wanted to kick Ryoma and hold him close. He couldn't think straight. He hated this feeling.

For once, Ryoma was actually concerned from a lack of answer. He kept eyeing at Momoshiro until he felt like he had to say something, anything.

"Hey, hey. It's pretty rude to go silent after- "

"Drop it. You'll just get hurt."

This time it was Ryoma who was out of words. He could hardly believe his ears. His friend who was usually so happy and goofy had suddenly become like a different person. He wouldn't look back at him, and a shadow covered his eyes.

Ryoma took a deep breath as he felt blood rushing through his system. He sent a sharp look at his senior's way; he wasn't going to accept this kind of treatment. "Why would you say something like- "

"He won't like you back!" Momoshiro finally exclaimed, glaring back at him with wide eyes. "Even if he wasn't so stupid and actually realized there's more to life than training, he wouldn't like you! You're just a kid, you- ", he drew a breath, trying to concentrate on how to talk. "He likes older women!"

As mature as he was, Ryoma couldn't think of a smart reply after a shock like this one. "S-Shut up! You don't know him!"

Grabbing his arm, Momoshiro pulled him closer and forced Ryoma to look at him. "I've known him longer than you. Nothing good will come out of that."

Ryoma didn't like the serious tone in his voice, and even less the pain in his arm. "What's up with you? W-Why are you so mean- "

The child-like accusation wrenched his heart painfully. "I don't want you to get hurt!"

Anger getting the better of him, Ryoma twisted his arm free and rubbed the reddened skin, glaring daggers at this so-called friend. "Too late." He said with a barely audible voice and took a step back, turned to the opposite direction and ran off. He could hear his last name being shouted behind him. He ran all the way to his house without slowing down.

As he slammed the door shut behind him, Ryoma cursed out loud and opened the zipper of his bag, picking up the first racket he got his hands on and threw the rest on the floor before loudly stomping across the house, all the way to the backyard.

He kept sending heavy shots against the wall, imagining Momoshiro's face on each ball he hit, until the doorbell rang and woke him up from his trance. Slightly panicking, Ryoma dropped his racket and hurried to the door, practically swinging it open. He became aware that he must've looked like hell only when it was too late.

Behind the door was a very taken aback Kaidou. They stared at each other, both breathing heavily until the other would speak.

"I'm here." Kaidou finally said, hesitating.

"U-Un." Ryoma nodded and quickly moved to the side as he realized he was blocking the way. Suddenly, he felt really awkward, and Momoshiro was fully to blame for that.

Kaidou bowed slightly and excused himself for intruding before stepping inside, just like the polite boy he was. Something about that made Ryoma smile again, and he let out a breath he hadn't realized he'd held, all the former tension suddenly leaving him.

"Such a polite young man you are." He smirked.

Heat gathering on his face, Kaidou kicked his shoes off and threw his sweaty towel on Ryoma's face.

"Shut up."


	4. Challenge Reversed

Ryoma only laughed at the rude gesture; his senior's embarrassment was more amusing than threatening. He peeled the damp towel off his face and threw it into the laundry basket before padding after Kaidou like a small animal. There was a glint in his eyes, just like during an exciting tennis match.

Kaidou didn't need to turn around to know he was being followed. Just like he wouldn't have noticed, he kept on walking calmly to the living room and seated himself on the floor and allowed himself to take a more comfortable position. Ryoma plopped down right next to him, his legs sprawled on the floor with no hint of grace.

This didn't go unnoticed. Kaidou snorted and slapped the boy's knee lightly, causing him to jolt and pull his knees up to his chest. He placed a protective hand around his legs and faked a hurt look.

"What was that for?"

"Seat yourself properly. Especially in front of guests." Kaidou grunted and turned to open his bag, pulling out a notebook with writing equipment and set them neatly on the coffee table. Ryoma made a face at that, finding it unbelievable that he'd start doing his homework right after running for hours.

Annoyed by Ryoma's gawking, Kaidou turned sharply to glare at him. "Stop that." He commanded and let out a flustered sigh, dropping his pencil for a moment so he could take off his bandana. Since the keen eyes wouldn't leave him, he threw the headwear on Ryoma's face, blocking his view.

"I'm sensing a pattern here." Ryoma mumbled against the cloth and let it slide off his unimpressed face. He opened his mouth to speak, but fell silent right away. His eyes wandered down on his hands to study the green cloth, and fiddled it between his fingers for a while before attempting to speak again.

"It's pretty rude to ignore someone in their own house you know..."

The pencil stopped, not finishing the character it had began. Kaidou's tongue quickly swiped over his upper lip as he contemplated on what to do. He exhaled deeply and erased the failed character, starting over. "I'm hungry."

Ryoma blinked at the blunt statement, and soon realization hit him. "AHH- "

Taken aback by the sudden exclamation, Kaidou messed up his writing again and mentally cursed at that. "What?!" He yelled back, glaring at his junior with wide eyes.

"I forgot that I had to eat."

Both stared at each other, expressionless.

"Do you have hay for brains, stupid brat."

"Oi, watch your tone."

"'Oi, watch your tone, _Senpai.'_" Kaidou clicked his tongue and poked Ryoma's cheek with the pointy end of his pencil, drawing a whine out of him.

Ryoma rubbed his cheek, a displeased look in his eyes. "Yes, Senpai..." He muttered and slowly stood up, using Kaidou's shoulder as support. (And purposedly made him mess up again.)

He eyed at the bandana in his grip and grinned. He brought it up against his forehead and tied it around his skull; well, attempted to do so, anyway. The knot was too loose and the cloth was over his eyes before he noticed. "Che."

Kaidou looked up and it took serious effort trying not to laugh at the sight. It seemed like he wouldn't be able to finish his homework while in this household, but... perhaps it would be alright, just this once.

He yanked the younger boy down by the hem of his shirt and completely ignored his complaining about pain and violence. He slid the bandana off Ryoma's head and deftly folded it from the middle, leaving it on his lap. He gave a quick glance at Ryoma's hair before brushing his finger's through the messy black locks, tidying them up.

Ryoma stopped complaining mid-sentence and stared at his senior's face which was now so very close to his own, his head slightly nodding from the soft caresses. He was certain that the temperature of the room increased significantly just then.

Determining it was good enough, Kaidou took the bandana back into his hands and placed it over Ryoma's head, his arms around him as he tied it up properly. He was too absorbed into his task to notice the look he was given, full of curiosity and wonder.

Never before had the young Echizen been able to look at his senior from up close, and now that the chance was given he went and took it. He took note of the dark lashes decorating the steely gray eyes and the light wrinkles around them. The usual dent between his brows was there too, as Kaidou had this habit to frown whenever he was concentrating. Well, doing anything, really.

His gaze trailed along the strong jaw, and he frowned as well. Something was different. He noticed the same change of features on the bridge of his nose and the bones of his cheeks. They were sharper than he remembered, more masculine. He hadn't given his senior a permission to grow and change. Not when his own frame was still one of a child.

"Done."

Ryoma flinched slightly, snapping out of his little zone. He looked at Kaidou straight in the eye, like a deer caught in the headlights. Kaidou didn't seem to notice anything as he simply patted Ryoma on the shoulder and turned back to his work. "You're good to go."

"Uh." The boy managed, as nothing else would come out of him. His hand traveled absent-mindedly to his head, feeling the fabric about. "I'll... go heat up some leftover sukiyaki." He cleared his throat, bringing the normal edge back to his voice. "Get picky and starve."

He heard a grunt as a response, and Ryoma could only guess it meant approval. He'd become rather good at understanding the mysterious language of Kaidou Kaoru, which mostly consisted of grumbles and glares.

As Ryoma passed a mirror, he had to take a step back and give himself a look. It wasn't bad, really, but no one could pull it off as well as Kaidou - in Ryoma's opinion, at least. He tilted his chin slightly, trying to look for an angle that would resemble the similar sharpness to that of Kaidou's.

He furrowed his brows and glared, his pupils contracting. "Hah? You wanna go?" He imitated in a lower tone and leaned closer to the mirror, raising a fist at it.

"Stop talking to yourself, Echizen. One Ibu is more than enough."

Ryoma slapped a hand over his mouth, both embarrassed and amused. He could hear Kaidou mumbling something about creepy people, and trying to contain his laughter he fled to the kitchen.

* * *

When he walked back to the living room with two steaming bowls in his hands, the first thing Ryoma noticed was the lack of sound. The scribbling noise was gone. As he walked further into the room, he couldn't see Kaidou anywhere either.

_Strange, _Ryoma thought as he walked over to the coffee table to get rid of the hot dishes, immediately pulling his fingers away as the porcelain touched the table's surface. "Ow, ow, ow..." He quietly complained and blew cool air on his poor hands.

That was when his gaze fell on the couch and he could practically feel all the colour leaving his face as he got startled by the figure lying on the furniture.

Well, _figures._

As unbelievable as it was, there they were, sleeping soundly. Karupin was comfortably curled up on Kaidou's chest, both breathing softly. The boy's right hand was still resting on the animal's soft fur... and it was covered in angry red scratches.

Shaking his head and sighing, Ryoma sat down on the edge and poked at the Himalayan. "Karupin..." He scolded under his breath, even if it was too late for the cat to realize what it had done wrong. Not that it would actually obey even if it did.

The furry creature opened it's eyes immediately and stretched it's legs, letting out a quiet 'hooara' before jumping off Kaidou's body and padding out of the room. The boy mumbled something in his sleep and stirred, but didn't awaken.

Ryoma glanced at the warm food resting on the table and reached towards his senior, yet he stopped before his fingertips could touch the fabric of the other's clothes. He didn't have the heart to disturb his rest, especially when he looked so much younger and so peaceful like that.

Carefully, Ryoma rested his head on Kaidou's chest, on the very same spot Karupin had been on just a few moments ago. _This isn't right, is it... _He bit his lower lip and was ready to move until a warm hand was placed on the back of his head, halting his movement completely.

"Karupin..." Kaidou mumbled in his sleep as he lightly stroked the soft hair on Ryoma's nape.

_Great. I've become Karupin._

Even if he felt a little devastated to find out who was the subject of Kaidou's dreams, Ryoma figured he could play a substitute Karupin at least this one time.

* * *

**AN: **I missed writing Kaidou. More jealousy issues and a snooping Fuji in the next chapter!


End file.
